The Florida Republican speaks at Ronald Reagan Presidential Library in Simi Valley during a swing through California to raise money — and his national profile.

It's hard for Marco Rubio to escape speculation about his prospects for the Republican vice presidential nomination, so the Florida senator joked about it Tuesday on a California trip aimed at raising his national profile.

"I have no interest in serving as vice president for anyone who could possibly live all eight years of the presidency," Rubio told a gathering at the Reagan Presidential Library in Simi Valley. Laughter spread across the room.

A Latino newcomer from a large swing state, Rubio, 40, ranks near the top of many lists of his party's contenders for presidential running mate, even as he insists he will stay in the Senate.

The son of immigrants who fled Cuba under Fidel Castro, Rubio rode into office last year as one of the best-known conservatives backed by the then-nascent "tea party" movement. Rubio has played down his tea party ties in recent months, but he did not shy away from the group in response to a question at the library.

"As maligned as it may be in the mainstream media," he said, "the tea party movement has and continues to be a collection of everyday Americans from all walks of life who believe that this is the greatest nation in the history of the world, that it can stay that as long as it wants to, but that that's not where it's headed, and it needs to reverse quickly."

Rubio's speech to just over 1,000 people at the library was the public highlight of a California visit that was also a quest for campaign money. Rubio has been collecting donations for his reelection campaign and for the National Republican Senatorial Committee at private events this week in San Francisco, Silicon Valley and Los Angeles.

Another signal of Rubio's expanding political horizons is the political action committee that he formed earlier this month. The committee, the Reclaim America PAC, can finance his national travel and provide a source of money for donations to allies who may prove helpful to him in the future.

Last year, Rubio ran a conservative insurgent's campaign for the U.S. Senate seat against Charlie Crist, then Florida's Republican governor. Rubio's popularity ultimately led Crist to bolt the party and run unsuccessfully as an independent.

In his remarks at the library, Rubio's theme was small government, with calls for unspecified cuts in Social Security and Medicare.

"These changes will not be easy," he told the crowd.

In a swipe at former President George W. Bush, whom he did not name, Rubio blamed a succession of administrations for allowing government to grow beyond its means.

"I know that it's popular in my party to blame the president, the current president," he said. "But the truth is that the only thing this president has done is accelerate policies that were already in place, and were doomed to fail."

Rubio paid the obligatory tribute, given the location, to the late President Reagan, saying he had defined the proper role of government "better than any American has ever done before." Rubio did not mention Reagan's repeated straying from the current Republican orthodoxy of opposition to all tax increases.

Rubio's event got off to a rough start. He was escorting Nancy Reagan into the room to a standing ovation when the 90-year-old former first lady suddenly fell, nearly to the ground. The crowd gasped and fell silent for a long pause before the applause resumed as she took her seat.

After his remarks, Rubio took a handful of pre-selected questions from the audience, starting with an inquiry on his interest in the vice presidency, which led him to profess his love for the Senate.

"What happens in politics is the minute you start thinking there's something else out there for you, it starts affecting everything you do," he said. "All of a sudden, maybe you're afraid to take a position on a certain issue because it imperils your opportunity to do that something else. So the reality of it is, I'm not going to be the vice presidential nominee. But I look forward to working for whoever our nominee is."